8.8 Drum to Disc swap

Haleyes · Oct 4, 2007

Ok, don't hate........here goes.......I am a Jeep guy! There, I said it.
Thought I'd get your guys expertise.

I currently have a drummed 8.8 under my XJ. It is out of a 2001 SporTrac(31 spline). I have the opportunity to get my hands on some discs off of a Crown Vic 8.8(28 spline). If it matters, I *think* the Crown Vic is a 1994 model. I'm not 100% on that though.

Is this be a direct swap for me? Will the Crown Vic backing plates bolt right up to my 8.8 out of the SporTrac? Any other advise is welcome as well.
TIA guys. I apperciate it.

Hale

4x4junkie · Oct 5, 2007

No, the backing plate bolt pattern on a 28 spline axle is different than a 31 spline (likely due to the bigger wheelbearing on the 31).

Discs off a '95-'01 Explorer axle I would think would be a direct fit though (they fit the earlier '91-'94 Explorer drum axle anyway).

AllanD · Oct 8, 2007

Uhhh.... Actually the Axle tubes on the crown VIC axles use the larger mounting flange of the 8.8" axle.

a Crown Vic uses brakes that are nearly identical to those used on the explorer,
the only odd thing is that the crown Vic uses the SAME backing plate and caliper
on BOTH sides of the vehicle!

the parking brake cable is routed around to the BACK of the passenger side backing plate

Basically the Crown Vic uses TWO Explorer Drivers side backing plates and Calipers.
(the caliper is on the back on the left and on the front on the right))

Will it bolt on? Yup!

BTW, don't feel bad about being a jeep guy, I've sold four complete
Explorer Disc axles. all four of them to Jeep owners

Compared to a Ford 8.8" axle even a dana44 is a complete POS.
(a D44 is roughly equivelent in strength to a Ford 7.5")

AD

Haleyes · Oct 9, 2007

Thanks!

Thanks for the input guys. After reading 4x4junkies post I was concerned. However, after I got the tape measure out and measured the bolt patterens, they are identical. So it looks like it should swap right on. You are also correct about the backing plates. The drivers side is on the back side and the passanger side is in front of the axle, which in my opinion......is no big deal.
Another thing I have seen on another forum is that the Crown Vic uses some goofy metric thread on the brake lines. Do you know anything about this?
I would think that I should be able to swap on some Explorer hoses if this is the case. No?

I got the of my stuff for a case of Barley Water, so I don't have much invested in it. The calipers are basically "cores" for me. I plan on getting new rotors and of course pads. I think the hoses are OK so if I can use them, I will.

Thanks again guys!

Hale

4x4junkie · Oct 9, 2007

Oops, I guess I was wrong on that.

Is this unique to just the Vic? I've never seen the large pattern on any other 28 spl 8.8. I've never seen any metric brake hoses on one either, but I guess I can't be sure about the Vic (my Explorer stuff has normal 3/8 x 24 threaded stuff on it, that I know).

Haleyes · Oct 15, 2007

Swap complete!

Well, all is complete. Wasn't exactly a bolt on deal, but it was close. The backing plate bolt pattern was not the same, but very close........it is now the same.

The hardest part of the whole thing was getting the c-clip out of the Aussie Locker!

I now have a set of drum brakes to get rid of if anyone is interested. They are off of a 8.8. The 8.8 is out of a 2001 SporTrac. I didn't measure them but they are at least 10" drums. I can get pics and more details if anyone is intersested.

Hale

Haleyes · Oct 26, 2007

Here are a few pics of the swap. You can see where I had to "massage" the backing plates to get them to sit flush on the tube. So far so good, I can tell a big difference. I didn't mess with the e-brake. I never used it anyway.

AllanD · Oct 29, 2007

Yeah, the Vic/Marquis/towncar are the oddballs.

Yeah, I checked and the backing plates are drilled slightly differently

But no, the stuff won't work on Ranger axle tubes, the flanges on 28-spline Ranger housings are too small.

AD

8.8 Drum to Disc swap

Haleyes

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AllanD

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Haleyes

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